In 1949, RCA Victor gave music a shot in the arm with the introduction of the first new phonograph record format in decades: the 45 rpm "single."  As opposed to the unwieldy and fragile 12" 78 rpm discs, the 7" 45s, were perfect for jukeboxes and portable players.  Now you could take your music anywhere!  Of course, you couldn't use your 78 needle…

And if you're going to be taking your music with you, you've got to have something to carry them in, don't you?  I've now got three of these nifty hinged cardboard boxes, the smaller of which carry around 40, and the bigger one twice that.

This one, which I use to carry my 1958 singles, even has a decal of Dick Clark on the cover!  It also came with numbered dividers so you can maintain a library on paper for easy reference.

So when you want to listen to your music on the go, simply clasp your boxes and head on out for a party!